Battery cell, battery module, battery pack, device using battery cell as power supply, and method for assembling battery cell

ABSTRACT

The present disclosure relates to a battery cell to alleviate the problem of impurities falling into an electrode assembly. Wherein, the battery cell includes: an electrode assembly including a tab and a cell body, wherein the tab is connected to the cell body; a cover plate assembly including an electrode terminal and a cover plate, wherein the electrode terminal is disposed on the cover plate; a connecting sheet connected between the tab and the electrode terminal, the connecting sheet includes a first connecting portion and a second connecting portion, wherein the first connecting portion is connected to the tab, and the second connecting portion is connected to the electrode terminal; an insulating pallet disposed between the cell body and the connecting sheet; and an insulation member disposed between the insulating pallet and the second connecting portion.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.17/058,490, filed on Nov. 24, 2020, which is a National Stage Entry ofInternational Patent Application No. PCT/CN2019/120642, filed on Nov.25, 2019. The aforementioned patent applications are incorporated byreference in their entirety.

TECHNICAL FIELD

The present disclosure relates to the field of batteries, and inparticular to a battery cell, a battery module, a battery pack, a deviceusing the battery cell as a power supply, and a method for assemblingthe battery cell.

BACKGROUND

Metal chips are produced during a welding process of a connecting sheetand a top cover. In order to prevent metal chips from falling into anelectrode assembly, a common method is to apply glue at a weldingposition. However, currently, there is no glue in the industry that maycompletely resist an electrolyte.

SUMMARY

According to one aspect of the embodiments of the present disclosure,the battery cell includes: an electrode assembly including a tab and acell body, wherein the tab is connected to the cell body; a cover plateassembly including an electrode terminal and a cover plate, wherein theelectrode terminal is disposed on the cover plate; a connecting sheetconnected between the tab and the electrode terminal, the connectingsheet includes a first connecting portion and a second connectingportion, wherein the first connecting portion is connected to the tab,and the second connecting portion is connected to the electrodeterminal; an insulating pallet disposed between the cell body and theconnecting sheet; and an insulation member disposed between theinsulating pallet and the second connecting portion.

In some embodiments, the insulating pallet and the connecting sheet bothabut against the insulation member.

In some embodiments, the insulating pallet includes a body portion and acarrying portion connected to the body portion, wherein the body portionabuts with the cell body, the carrying portion protrudes in a directionthat is closer to the second connecting portion than to the bodyportion, and the insulation member is disposed between the carryingportion and the second connecting portion.

In some embodiments, the second connecting portion protrudes in adirection that is closer to the electrode terminal than to the firstconnecting portion, and a first groove is provided on one side of thesecond connecting portion proximate to the electrode assembly.

In some embodiments, the insulation member covers an open end of thefirst groove.

In some embodiments, the insulating pallet includes a carrying portionprotruding towards the second connecting portion, and the carryingportion and the first connecting portion jointly limit the insulationmember.

In some embodiments, the insulation member is disposed within the firstgroove.

In some embodiments, the insulating pallet includes a carrying portionprotruding towards the second connecting portion, the carrying portionprojects into the first groove, and the carrying portion and a bottom ofthe first groove jointly limit the insulation member.

In some embodiments, the insulation member includes foam, rubber cloth,or solid glue.

In some embodiments, the insulation member includes a solid rubber stripor a colloidal object formed by gumming and curing on the insulatingpallet.

In some embodiments, the insulation member includes a colloidal objectformed by gumming and curing on the insulating pallet, and a pluralityof second holes are provided on an area of the insulating pallet that isin contact with the insulation member, so as to prevent overflow ofglue.

In some embodiments, the insulating pallet further includes an insertportion, which is connected to a side of the body portion, and isfarther from the cell body than the body portion, and at least a part ofthe tab is located between the insert portion and the cell body.

According to one aspect of the embodiments of the present disclosure, abattery module includes the battery cell described above.

According to one aspect of the embodiments of the present disclosure, abattery pack includes the battery module described above.

According to one aspect of the embodiments of the present disclosure, adevice using the battery cell described above as a power supply.

According to one aspect of the embodiments of the present disclosure, amethod for assembling the battery cell described above, includes:providing a connecting sheet and an electrode assembly, and connecting afirst connecting portion of the connecting sheet with a tab of theelectrode assembly; providing a cover plate assembly, and connecting asecond connecting portion of the connecting sheet with an electrodeterminal of the cover plate assembly; providing an insulation member,and disposing the insulation member on one side of the second connectingportion; and providing an insulating pallet, so that the insulationmember is disposed between the cell body and the connecting sheet.

According to one aspect of some embodiments of the present disclosure,the battery cell includes an electrode assembly, a cover plate assembly,a connecting sheet, an insulating pallet, and an insulation member. Theinsulation member is disposed between the insulating pallet and thesecond connecting portion of the connecting sheet. The insulation memberis configured to catch impurities falling from the second connectingportion, thereby preventing short-circuit when the impurities enter theelectrode assembly and improving the safety performance of the batterycell.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded schematic view of a battery cell providedaccording to some embodiments of the present disclosure;

FIG. 2 is a schematic cross-sectional view of a battery cell providedaccording to some embodiments of the present disclosure;

FIG. 3 is a schematic cross-sectional view of a battery cell providedaccording to other embodiments of the present disclosure;

FIG. 4 is a schematic view of an insulating pallet provided according tosome embodiments of the present disclosure;

FIG. 5 is a deployed schematic view of a battery cell during assemblyprovided according to some embodiments of the present disclosure;

FIG. 6 is a partially enlarged schematic view of an insulating palletprovided according to some embodiments of the present disclosure;

FIG. 7 is a schematic view of a cover plate provided according to someembodiments of the present disclosure;

FIG. 8 is a schematic view of a battery module provided according tosome embodiments of the present disclosure;

FIG. 9 is a schematic view of a battery pack provided according to someembodiments of the present disclosure;

FIG. 10 is a schematic view of a vehicle provided according to someembodiments of the present disclosure.

DETAILED DESCRIPTION

Next, the technical solution in the embodiments will be explicitly andcompletely described in combination with the accompanying drawings inthe embodiments of the present disclosure. Apparently, the describedembodiments are merely part of the embodiments of the presentdisclosure, rather than all the embodiments. On the basis of theembodiments of the present disclosure, all the other embodimentsacquired by a person skilled in the art on the premise that no inventiveeffort is involved fall into the scope protected by the presentdisclosure.

In the description of the present disclosure, it is necessary tounderstand that, the azimuth or positional relations indicated by theterms “center”, “transverse”, “longitudinal”, “front”, “rear”, “left”,“right”, “up”, “down”, “vertical”, “horizontal”, “top”, “bottom”,“within”, “outside”, which are based on the azimuth or positionalrelations illustrated by the drawings, are only for facilitatingdescription of the present disclosure and simplifying the description,rather than indicating or implying that the device or element referredthereto has to present a particular azimuth, and be constructed andoperated in a particular azimuth, so that it cannot be understood aslimiting the protection scope of the present disclosure.

The present disclosure provides a battery cell, a battery module, abattery pack, a device using the battery cell as a power supply, and amethod for assembling the battery cell to alleviate the problem ofimpurities falling into an electrode assembly.

As shown in FIG. 1 , in some embodiments, a battery cell is provided.The battery cell includes a housing 1, an electrode assembly 2, a coverplate assembly 3, a connecting sheet 4, an insulating pallet 5, and aninsulation member 6.

The housing 1 is formed with a cavity 11, and the housing 1 has an openend. The electrode assembly 2 is disposed within the cavity 11. Thecover plate assembly 3 is located at the open end of the housing 1 andcovers the electrode assembly 2, so as to enclose the electrode assembly2 within the housing 1. The connecting sheet 4 is disposed between thecover plate assembly 3 and the electrode assembly 2 and configured todirect the electricity produced by the electrode assembly 2 to the coverplate assembly 3. Some parts of the insulating pallet 5 are disposedbetween the cover plate assembly 3 and the electrode assembly 2, whileother parts of the insulating pallet 5 are disposed between theconnecting sheet 4 and the electrode assembly 2. The insulation member 6is disposed between the insulating pallet 5 and the connecting sheet 4.

The electrode assembly 2 includes a tab 21 and a cell body 22, whereinthe tab 21 is connected to the cell body 22.

The cell body 22 includes a positive pole piece, a negative pole piece,and a diaphragm. Both the positive pole piece and the negative polepiece include an application area. The active substance of the positivepole is applied to the application area of the positive pole piece, andthe active substance of the negative pole is applied to the applicationarea of the negative pole piece. The diaphragm is an insulator disposedbetween the positive pole piece and the negative pole piece. Thediaphragm is configured to space apart the application area of thepositive pole piece from the application area of the negative polepiece. The positive pole piece, the diaphragm, and the negative polepiece are sequentially stacked and wound to form the cell body 22.

The tab 21 includes a positive pole tab and a negative pole tab. The endof the positive pole piece has a blank area not applied by the activesubstance of the positive pole, and a plurality of blank areas of thepositive pole piece are connected together to form the positive pole tabof the electrode assembly 2. The end of the negative pole piece has ablank area not applied by the active substance of the negative pole, anda plurality of blank areas of the negative pole piece are connectedtogether to form the negative pole tab of the electrode assembly 2.

Optionally, the material of the positive pole piece includes aluminumfoil. The material of the negative pole piece includes copper foil.

Optionally, the active substance of the positive pole piece includeslithium cobaltate. The active substance of the negative pole pieceincludes silicon.

The cover plate assembly 3 is located at the open end of the housing 1and covers the electrode assembly 2, so as to enclose the electrodeassembly 2 within the housing 1. The cover plate assembly 3 includes anelectrode terminal 31 and a cover plate 32. The electrode terminal 31 isprovided on the cover plate 32. The cover plate 32 is configured tohermetically connect with the housing 1, so as to enclose the electrodeassembly 2 within the housing 1.

As shown in FIG. 7 , the cover plate 32 is provided with two first holes321 at intervals. The electrode terminal 31 includes a positiveelectrode terminal and a negative electrode terminal. The positiveelectrode terminal passes through one of the two first holes 321, andthe negative electrode terminal passes through the other of the twofirst holes 321. The positive electrode terminal is conductive incorrespondence with the positive pole tab, and the negative electrodeterminal is conductive in correspondence with the negative pole tab.

As shown in FIG. 1 , the cover plate 32 is also provided with anexplosion-proof valve 33. Optionally, the explosion-proof valve 33 isdisposed between the positive electrode terminal and the negativeelectrode terminal.

Since a chemical substance, such as an electrolyte, is injected into thehousing 1 of the battery cell, a large amount of mixed gas and liquidmay be produced during the charging and discharging process, whichcauses that a pressure is continuously accumulated inside the housing 1and it is extremely likely that explosion occurs. In the presentdisclosure, the cover plate 32 is provided with an explosion-proof valve33. When there is an excessive internal pressure of the battery cell,the explosion-proof valve 33 is opened, so that the mixed gas and liquidproduced by charging and discharging are rapidly discharged through theexplosion-proof valve 33, thereby preventing explosion due to anexcessive internal pressure of the battery cell.

Optionally, the cover plate 32 is configured to a flat plate shape.

In some embodiments, as shown in FIGS. 5 and 7 , the cover plateassembly 3 further includes an insulating member 34, which is disposedbetween the cover plate 32 and the cell body 22, thereby preventingoccurrence of short-circuit when the cover plate 32 is in contact withthe cell body 22.

As shown in FIGS. 1 to 3 , the connecting sheet 4 is connected betweenthe tab 21 and the electrode terminal 31. The connecting sheet 4 isformed of a conductive material and configured to connect the conductivetab 21 with the electrode terminal 31.

The connecting sheet 4 includes a first connecting portion 41 and asecond connecting portion 42. The first connecting portion 41 isconnected to the tab 21, and the second connecting portion 42 isconnected to the electrode terminal 31.

The second connecting portion 42 protrudes in a direction that is closerto the electrode terminal 31 than to the first connecting portion 41,and the second connecting portion 42 is provided with a first groove 421at one side proximate to the electrode assembly 2.

Optionally, the first connecting portion 41 is configured to a flatplate shape.

The first connecting portion 41 of the connecting sheet 4 is connectedto the tab 21, and other parts of the connecting sheet 4 than the firstconnecting portion 41 is spaced apart from the cell body 22 by theinsulating pallet 5, so as to prevent occurrence of short-circuit. Thesecond connecting portion 42 of the connecting sheet 4 is connected tothe electrode terminal 31.

Since the tab 21 includes a positive pole tab and a negative pole tab,and the electrode terminal 31 includes a positive electrode terminal anda negative electrode terminal, one connecting sheet 4 is providedbetween the positive electrode terminal and the positive pole tab so asto conduct the positive electrode terminal with the positive pole tab,and another connecting sheet 4 is provided between the negativeelectrode terminal and the negative pole tab so as to conduct thenegative pole tab with the negative electrode terminal.

Some parts of the insulating pallet 5 are disposed between the cell body22 and the connecting sheet 4. The insulating pallet 5 spaces theconnecting sheet 4 apart from the cell body 22 so that the connectingsheet 4 is connected to the cell body 22 through the tab 21 rather thanthat the connecting sheet 4 is directly connected to the cell body 22,thereby avoiding short-circuit when the connecting sheet 4 is directlyconnected to the cell body 22.

Other parts of the insulating pallet 5 are located between the coverplate assembly 3 and the cell body 22, and configured to implementisolating the cover plate assembly 3 from the cell body 22, so that thecover plate assembly 3 is connected to the cell body 22 through theelectrode terminal 31, the connecting sheet 4 and the tab 21, ratherthan that the cover plate assembly 3 is directly connected to the cellbody 22, thereby avoiding short-circuit when the cover plate assembly 3is directly connected to the cell body 22.

The insulation member 6 is disposed between the insulating pallet 5 andthe second connecting portion 42 of the connecting sheet 4.

Since there is a need to use laser welding during the assembly processof the battery cell, impurities (e.g. metal chips) may be producedduring the laser welding process. At the same time, during the assemblyprocess, foreign impurities might also fall into the first groove 421 ofthe second connecting portion 42. When the battery cell vibrates,impurities on the second connecting portion 42 might fall into theelectrode assembly 2, thus causing a short-circuit risk. Therefore, ifthe insulation member 6 is disposed between the insulating pallet 5 andthe second connecting portion 42 of the connecting sheet 4, even ifimpurities of the second connecting portion 42 fall, they may also becaught by the insulation member 6, thereby avoiding short-circuit whenimpurities enter the electrode assembly 2, and improving the safetyperformance of the battery cell.

In a normal placement state of the battery cell, the insulation member 6is pressed against the insulating pallet 5 due to a gravitationaleffect, and there might be a gap between the connecting sheet 4 and theinsulation member 6. In order to prevent shaking or misplacement of theinsulation member 6 due to vibration of the battery cell, and improvethe positional stability of the insulation member 6, the insulatingpallet 5 and the connecting sheet 4 both abut against the insulationmember 6.

As shown in FIGS. 2 and 3 , the insulating pallet 5 includes a bodyportion 51 and a carrying portion 52 connected to the body portion 51.The body portion 51 abuts with the cell body 22, and the carryingportion 52 protrudes in a direction that is closer to the secondconnecting portion 42 than to the body portion 51. The insulation member6 is disposed between the carrying portion 52 and the second connectingportion 42. Impurities falling from the second connecting portion 42 maybe caught by the insulation member 6, thereby avoiding short-circuitwhen impurities enter the electrode assembly 2 and improving the safetyperformance of the battery cell.

Optionally, the body portion 51 is configured to a flat plate shape.

In some embodiments, as shown in FIG. 2 , the insulation member 6 coversthe open end of the first groove 421. The carrying portion 52 and thefirst connecting portion 41 jointly limit the insulation member 6.

Optionally, both the carrying portion 52 and the first connectingportion 41 abut against the insulation member 6. Furthermore, an areawhere the first connecting portion 41 is connected to a circumferentialside wall of the first groove 421 abuts against the insulation member 6.

In other embodiments, as shown in FIG. 3 , the insulation member 6 isdisposed within the first groove 421. The carrying portion 52 projectsinto the first groove 421, and the carrying portion 52 and the bottom ofthe first groove 421 jointly limit the insulation member 6.

Optionally, both the carrying portion 52 and the bottom of the firstgroove 421 abut against the insulation member 6.

In some embodiments, as shown in FIGS. 2 and 3 , the insulating pallet 5further includes an insert portion 53, which is connected to a side ofthe body portion 51, and is farther from the cell body 22 than the bodyportion 51. At least a part of the tab 21 is located between the insertportion 53 and the cell body 22. The insert portion 53 is provided toprevent short-circuit when the tab 21 is inserted into the cell body 22.

Optionally, the insert portion 53 is connected to the body portion 51through a transition section, and the surface of the insert portion 53is parallel to that of the body portion 51. Furthermore, the surface ofthe insert portion 53, the surface of the body portion 51, and thesurface of the carrying portion 52 are all parallel to each other.

As shown in FIGS. 4 and 6 , the insulating pallet 5 is further providedwith a hook 54 extending in the direction towards the cover plateassembly 3. As shown in FIG. 7 , the cover plate 32 is provided with aslot 322. The cover plate 32 is connected to the housing 1 in anenclosed manner, and the hook 54 on the insulating pallet 5 is connectedto the slot 322 on the cover plate 32.

Optionally, the hook 54 is disposed on the body portion 51 and locatedat an end portion of the insulating pallet 5. Since the body portion 51is proximate to the cell body 22 relative to the carrying portion 52 andthe insert portion 53, the body portion 51 is provided with a hook 54extending towards the cover plate assembly 3, and the space between thebody portion 51 of the insulation plate 5 and the cover plate assembly 3is subtly utilized without increasing the thickness of the insulationplate 5, and it is also unnecessary to individually provide a connectingsheet to connect the insulating pallet 5 with the cover plate assembly3, so that the structure is simple and the installation is convenient.

The insert portion 53 of the insulating pallet 5 isolates the tab 21from the cell body 22 and is fixed to the cover plate assembly 3, so asto ensure that the tab 21 and the cell body 22 are sufficiently spacedapart, thereby preventing a short-circuit risk when the tab 21 isinserted into the cell body 22.

As shown in FIG. 4 , the insulating pallet 5 is also provided with avent hole 55. The vent hole 55 is configured to expel the gas or liquidproduced by the battery assembly 2, and also configured to inject anelectrolyte into the battery assembly 2, and there is also a function oflessening the weight of the insulating pallet 5.

In some embodiments, at least two rows of vent holes 55 are provided inthe insulating pallet 5, with at least two vent holes for each row ofvent holes.

As shown in FIG. 5 , in a case where the battery cell includes twobattery cell bodies 22, the two battery cell bodies 22 are respectivelydisposed on both sides of the insulating pallet 5, and each of thebattery cell bodies 22 is connected to the tab 21. An insert portion 53is provided on both sides of the insulating pallet 5. Wherein, at leasta part of the tab 21 corresponding to one of the cell bodies 22 islocated between the insert portion 53 on one side of the insulatingpallet 5 and the cell body 22, and at least a part of the tab 21corresponding to the other cell body 22 is between the insert portion 53on the other side of the insulating pallet 5 and the cell body 22.

The body portion 51 of the insulating pallet 5 abuts with the cell body22, and two insert portions 53 are respectively provided on two oppositesides of the body portion 51, to form a wing-like shape, therebypreventing that the body portion 51 is pressed against the tab 21 andenabling to avoid that the insulating pallet 5 is too thick.

In some embodiments, as shown in FIG. 4 , the body portion 51 of theinsulating pallet 5 is configured to a strip shape, and two carryingportions 52 are provided at intervals in the length direction of thebody portion 51. One connecting sheet 4 is provided above acorresponding position of each carrying portion 52. One insert portion53 is provided respectively on both sides of the body portion 51corresponding to the positions where the two carrying portions 52 arelocated. One catch 54 for connection with the cover plate assembly 3 isprovided on both ends of the body portion 51 in the length direction.The vent hole 55 is disposed between the two carrying portions 52.

In some embodiments, the insulation member 6 includes foam, tape, orsolid glue.

In some embodiments, the insulation member 6 includes a solid rubberstrip.

In some embodiments, the insulation member 6 includes a colloidal objectformed by gumming and curing on the insulating pallet 5.

An area of the insulating pallet 5 that is in contact with theinsulation member 6, that is, an area where the insulating pallet 5 isgummed, is provided with a plurality of second holes 522, so as toprevent overflow of glue.

Further, as shown in FIG. 6 , a plurality of second holes 522 areprovided in the carrying portion 52, so as to prevent overflow of glueupon application of glue on the carrying portion 52.

The insulation member 6 which is formed of a soft material deformedadaptively according to the shape of the installation space, so as to beadapted to a narrow space within the battery cell.

In some embodiments, a method for assembling the battery cell describedabove is provided. The method includes: providing a connecting sheet 4and an electrode assembly 2, and connecting a first connecting portion41 of the connecting sheet 4 with a tab 21 of the electrode assembly 2;providing a cover plate assembly 3, and connecting a second connectingportion 42 of the connecting sheet 4 with an electrode terminal 31 ofthe cover plate assembly 3; providing an insulation member 6, anddisposing the insulation member 6 on one side of the second connectingportion 42 remote from the cover plate assembly 3; and providing aninsulating pallet 5 so that the insulation member 6 is disposed betweenthe cell body 22 and the connecting sheet 4.

In some embodiments, the step of providing a connecting sheet 4 and anelectrode assembly 2 includes: positioning the electrode assembly 2 withthe connecting sheet 4 such that the tab 21 is located on a first sideof the connecting sheet 4.

The step of providing the cover plate assembly 3 includes: positioningthe cover plate assembly 3 with the connecting sheet 4 such that theelectrode terminal 31 is located on a second side of the connectingsheet 4.

Wherein, the first side and the second side of the insulation member 6are opposite sides.

In some embodiments, the step of disposing the insulation member 6between the cell body 22 and the connecting sheet 4 includes: abuttingthe insulating pallet 5 with the first side of the insulation member 6,and abutting the connecting sheet 4 with the second side of theinsulation member 6, so as to fix the position of the insulation member6.

As shown in FIG. 5 , in a specific embodiment of the battery cell, themethod for assembling the battery cell includes: placing the cover plate32 of the cover plate assembly 3 on an assembly platform; respectivelyproviding the connecting sheet 4 above the positions of the twoelectrode terminals 33 on the cover plate 32; connecting the secondconnecting portion 42 of the connecting sheet 4 with the electrodeterminal 33; laying flat a cell body 22 on both sides of the cover plate32 respectively; connecting the first connecting portion 41 of theconnecting sheet 4 with the tab 21; providing the insulation member 6 onthe second connecting portion 42 of the connecting sheet 4; placing theinsulating pallet 5 above the connecting sheet 4 so that the insulationmember 6 is disposed between the cell body 22 and the connecting sheet4.

The cell bodies 22 on both sides of the cover plate 32 are flippedupwards by 90 degrees and combined together, while the tab 21 is foldedso that at least a part of the tab 21 is located between the insertportion 53 of the insulating pallet 5 and the cell body 22; removing theabove-described assembled members from the assembly platform and placingthem within the cavity 11 of the housing 1. The cover plate assembly 3is located at the open end of the housing 1, and the cover plate 32 isconnected with the housing 1 in an enclosed manner, so as to enclose theelectrode assembly 2 within the housing 1.

In some embodiments, as shown in FIGS. 5 and 7 , an insulating member 34is further provided between the cover plate 32 and the cell body 22, soas to prevent short-circuit when the cover plate 32 is in contact withthe cell body 22.

As shown in FIG. 8 , in some embodiments, a battery module 200 isprovided. The battery module 200 includes the battery cell 100 describedabove.

The battery module 200 includes a plurality of battery cells 100, atleast part of which are connected in series, and at least part of whichare connected in parallel.

As shown in FIG. 9 , in some embodiments, a battery pack 300 isprovided. The battery pack 300 includes the battery module 200 describedabove.

The battery pack 300 includes a first box cover 301 and a second boxcover 302. The first box cover 301 and the second box cover 302 areconnected to form an enclosed box. The battery module 200 is providedwithin the enclosed box formed by the first box cover 301 and the secondbox cover 302.

The battery pack 300 includes two or more battery modules 200, at leastpart of which are connected in series, and at least part of which areconnected in parallel.

As shown in FIG. 10 , in some embodiments, a device using a battery cellas a power supply is provided. The device includes the battery cell 100described above.

The devices using a battery cell as a power supply include a vehicle400, a ship, or the like.

It should be noted that “abutment” between two members in the presentdisclosure does not mean direct contact, and other members may also beprovided between the two members.

In the description of the present disclosure, it is necessary tounderstand that, such wordings as “first” and “second” which areconfigured to define the parts, are only intended to facilitatedistinguishing the above-described parts. Unless otherwise specified,the aforementioned wordings do not have particular meanings, and thuscannot be understood as limiting the protection scope of the presentdisclosure.

In addition, without having been explicitly denied, the technicalfeatures in one of the embodiments may be advantageously combined withone or more other embodiments.

Finally, it should be explained that: the aforementioned embodiments areonly configured to describe the technical solution of the presentdisclosure rather than limiting the same; although detailed explanationsare made to the present disclosure by referring to preferredembodiments, a common technical person in the art should understandthat: it is still possible to make amendments to the embodiments of thepresent disclosure or make equivalent replacements to part of thetechnical features; without departing from the spirit and scope of thepresent disclosure, they should all be covered in the scope of thetechnical solution for which protection is sought in the presentdisclosure.

What is claimed is:
 1. A battery cell, comprising: an electrode assemblycomprising a tab and a cell body, wherein the tab is connected to thecell body; a cover plate assembly comprising an electrode terminal and acover plate, wherein the electrode terminal is disposed on the coverplate; a connecting sheet connected between the tab and the electrodeterminal, the connecting sheet comprises a first connecting portion anda second connecting portion, wherein the first connecting portion isconnected to the tab, and the second connecting portion is connected tothe electrode terminal; an insulating pallet disposed between the cellbody and the connecting sheet; and an insulation member disposed betweenthe insulating pallet and the second connecting portion, wherein theinsulating pallet and the connecting sheet both abut against theinsulation member.
 2. The battery cell according to claim 1, wherein theinsulating pallet comprises a body portion and a carrying portionconnected to the body portion, wherein the body portion abuts againstthe cell body, the carrying portion protrudes in a direction that iscloser to the second connecting portion than to the body portion, andthe insulation member is disposed between the carrying portion and thesecond connecting portion.
 3. The battery cell according to claim 1,wherein the second connecting portion protrudes in a direction that iscloser to the electrode terminal than to the first connecting portion,and a first groove is provided on one side of the second connectingportion proximate to the electrode assembly.
 4. The battery cellaccording to claim 3, wherein the insulation member covers an open endof the first groove.
 5. The battery cell according to claim 4, whereinthe insulating pallet comprises a carrying portion protruding towardsthe second connecting portion, and the carrying portion and the firstconnecting portion jointly limit the insulation member.
 6. The batterycell according to claim 3, wherein the insulation member is disposedwithin the first groove.
 7. The battery cell according to claim 6,wherein the insulating pallet comprises a carrying portion protrudingtowards the second connecting portion, and the carrying portion projectsinto the first groove, and the carrying portion and a bottom of thefirst groove jointly limit the insulation member.
 8. The battery cellaccording to claim 1, wherein the insulation member comprises foam,rubber cloth, or solid glue.
 9. The battery cell according to claim 1,wherein the insulation member comprises a solid rubber strip or acolloidal object formed by gumming and curing on the insulating pallet.10. The battery cell according to claim 9, wherein the insulation membercomprises a colloidal object formed by gumming and curing on theinsulating pallet, and a plurality of second holes are provided on anarea of the insulating pallet that is in contact with the insulationmember, so as to prevent overflow of glue.
 11. The battery cellaccording to claim 2, wherein the insulating pallet further comprises aninsert portion, which is connected to a side of the body portion, and isfarther from the cell body than the body portion, and at least a part ofthe tab is located between the insert portion and the cell body.
 12. Abattery module comprising the battery cell according to claim
 1. 13. Abattery pack comprising the battery module according to claim
 12. 14. Adevice using the battery cell according to claim 1 as a power supply.15. A method for assembling a battery cell, comprising: providing aconnecting sheet and an electrode assembly, wherein the connecting sheetcomprises a first connecting portion and a second connecting portion,the electrode assembly comprises a tab and a cell body connected to tab;connecting the first connecting portion of the connecting sheet with thetab of the electrode assembly; providing a cover plate assembly, whereinthe cover plate assembly comprises an electrode terminal and a coverplate, the electrode terminal is disposed on the cover plate; connectingthe second connecting portion of the connecting sheet with the electrodeterminal of the cover plate assembly; providing an insulation member,and disposing the insulation member on one side of the second connectingportion; and providing an insulating pallet, so that the insulationmember is disposed between the cell body and the connecting sheet,wherein the insulating pallet and the connecting sheet both abut againstthe insulation member.